Method of and means for controlling systems of distribution.



Patented Nov. 7, I899.

O. A. BROWN.

' (Application filed u. 22, 1597.

METHOD OF AND IEANS FOR CONTROLLING SYSTEMS OF DISTRIBUTION.

(No Model.)

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UNITED STATES PATENT EFIcE.

CHARLES A. BROTVN, OF CHICAGO, ILLINOIS, ASSIGNOR TO THE TVESTERNELECTRIC COMPANY, OF SAME PLACE.

METHOD OF AND MEANS FOR CONTROLLING SYSTEMS OF DISTRIBUTION.

SPECIFICATION forming part of Letters Patent No. 636,241, dated November7, 1899.

Application filed March 22, 1897. fl -628,555. (No model.)

To all whom it may concern: dynamo, may be briefly described as consist-Be it known that I, CHARLES A. BROWN, a ing of a shunt-wounddynamo-electric macitizen of the United States, residing at Chichinesupplying current to a multiple-arc syscago, in the county of Cool; andState of Illitem of lighting. Connected with the field 55 5 nois,haveinvented a certain new and useful windings of the said main dynamo is asec- Improvement in Methods of and Means for ondary dynamo-electricmachine having com- Controlling Systems of Electrical Distribupoundfield-windings, one of which is contion, (Case No. 4,) of which thefollowing is a nected in a branch across the mains of the full, clear,concise, and exact description, refworking circuit, and the other isconnected 6o 10 erence being had to the accompanying drawin series withsaid circuit. By this arrangeing, forming a part of this specification.ment of circuits and apparatus the strength My invention relates to amethod of and of the fields of the main generator is conmeans forcontrolling systems of electrical trolled directly by the counterelectromotive distribution, and has for its object the acforce exertedby the secondary dynamo and 65 complishment of such control morereadily, indirectly, but ultimately, by the resultant efficiently, andwithout the waste involved in field produced in the secondary dynamo bysimilar combinations or systems previously the combined effects of thecompound windemployed in the art. ings as thus connected with thecircuit. The

My system, speaking more particularly, field-windings of the secondaryare capable 7o contemplates the control of the generative of variousproportionate arrangements, as is force of a dynamo-electric machineserving well known in the art, whereby the resultant as the maingenerator of a system of distribumagnetic field produced in said dynamountion by means of interposing a variable-curder differing conditions ofthe working cirrent-controlling factor in the field-circuit of cuit willautomaticallymaintain the requisite 75 2 5 said generator which isgoverned by the recounter electromotive force in the field-cirsultantmagnetism produced by helices concuit of the main genera-tor. nected inseries and in multiple with the said My invention further contemplatesthe ausystem. tomatic transfer of energy to and from the Multiple-arcsystems of electrical distribufield-circuit of the main dynamo to suitthe 80 tion have previously been regulated by means conditions of theworking circuits, which will of an interposed counter electromotiveforce be set forth later. in the field-circuit of the dynamo. The Iwillnow describe myinvention more parmeans for accomplishing this may bedeticularly by reference to the accompanying scribed as consisting of amain shunt-wound drawing, which diagrammatically illustrates 8 generatorwith a motor of similar type conmeans for practicing the same.

nected in its field-circuit, the said motor be- The main generator A isprovided with ing adapted to interpose a variable counter field-winding13, connected in shunt with the ele'ctromotive force in the mainfield-circuit working circuit. The armature C of a secby means of anelectro-magnetic brake which ondary dynamo-electric machine C is con- 904o acts upon the armature-shaft of the motor nected in series with thefield-Winding B, the and controls its rate of rotation. This method saidarmature being adapted to supply the of regulating the fiow of currentthrough the resistance in the main field-circuit of dynamo field-coilsof the main generator necessarily A. The secondary dynamo is providedwith involves considerable waste of energy and the compoundfield-windings C and C which 5 requires additional apparatus foroperating are respectively connected in series with the the brakedevice, both of which objections working circuit of the main generatorand in are avoided in the apparatus herein shown a branch across themains thereof. From the and described. brushes of dynamo A the mains D Dconduct The system illustrated in the accompanythe current to the lampsor translating detoo ing drawing, exemplifying one means for efvices E,connected in multiple are between fecting the control of the output ofthe main the said mains.

It is apparent with the above arrangement of circuits that the winding Cwill receive less current, thereby weakening its influence upon thefield, as more translating devices E are thrown out of circuit, while,on the contrary,winding 0 being connected directly between the mainswill build up the strength of the field of dynamo C under the sameconditions, and in consequence the rate of rotation of its armature willtend to increase, which serves to introduce a corresponding increase ofcounter electromotive force into the field-circuit of dynamo A andreduces the flow of current therethrough.

I preferably wind the field-coils C O of the secondary dynamo-electricmachine differentially, properly proportioning them to secure the resultdesired and meet the varying conditions of different circuits, and willdescribe them as thus arranged in the system shown, although I do notdesire to be understood as limiting my invention to this arrangement ofthe compound windings in dynamo C. The said windings being differential,immediately more translating devices are cut into circuit winding C willreceive more current, while winding 0 will receive proportionally less.This weakens the field of dynamo 0, resulting in a correspondingreduction in the counter electromotive force exerted by its armature,which permits more current to flow through the winding B and rapidlybuilds up the field of the main dynamo. Conversely, should less currentbe demanded by the working circuit the influence of the winding iscorrespondingly weakened, the counter electromotive force of O rapidlyincreases, and the flow of current through the field-coils B of the maindynamo is reduced, thus automatically adjusting the generation ofelectromotive force to the requirements of the circuit and supplying atall times to each of the translating devices then connected in circuit aconstant amount of current.

Having now detailed the electrical connections of the present system, Iwill consider a further feature of my invention, which contemplates thetransference to the main circuit of energy developed by the secondarydynamo, and consists in connecting the two dynamos A and C with drivingmechanism whereby the armatures are rotated at rates of speedsubstantiallyconstant. Preferably both dynamos of the system are drivenby a single source of power at predetermined speeds, and as a result ofthis mechanical arrangement of the plant the secondary dynamo C willduring a portion of the time supply current to the circuit, while atother times it will operate as a motor and restore to the drivingmechanism a portion of the energy received in the form of excessivecurrent by the main field-circuit. Thus when a number of translatingdevices are cut out of the main circuit the resulting decrease in thecurrent flowing therein will, by reason of the differential windings ofthe secondary dynamo C,

increase the magnetic field strength of the latter, so that its armaturewill tend to rotate faster, and since the two machines A and (J aremechanically coupled to rotate at relatively constant speeds the maingenerator A will thus receive back in the form of mechanical energy theexcess of energy which it dolivers electrically to the secondary dynamoO. Vhen translating devices are being cut into the main circuit, on thecontrary, the field strength of the secondary dynamo C will be reduced,its counter electromotive force will be overcome, and the secondarydynamo will be driven as a generator by the common source of power,supplying electrical energy for the field-circuit of the main generatorA.

By means of the overcompounding effect obtainable in a system operatedas above I am enabled to secure automatic compensation for the necessarydrop in potential in the mains, do away with any brake device, andeffect a saving of energy otherwise consumed in the regulation of thesystem.

To those skilled in the art it will be seen that the method employed inthe abovedescribed system to effect the regulation of current and aneconomy in its operation is applicable to other apparatus, and I do notde sire to be understood as limiting myself to a system such as the oneshown, which serves merely to exemplify my invention. Variousmodifications of the above I accordingly consider within the spirit ofmy said invention.

Having thus described specific means for practicing my invention, whatIclaim as new, and desire to secure by Letters Patent, is-

1. The method of controlling the currentgenerative power of adynamo-electric machine, which consists in supplying the fieldcircuitofsuch machine with electrical energy derived from the main circuitthereof, interposing in such derived field-circuitan armature exerting avariable electromotive force adapted to alter the flow of currentthrough said field-circuit and effecting the alteration of the value ofsaid current by means of the resultant magnetic influence of currentsflowing in series and in parallel with the controlled circuit of saiddynamo-electric machine, substantially as described.

2. The herein-described method of controlling the generative force of adynamo-electric machine, which consists in shunting a portion of thecurrent from said machine through the derived field-circuit thereof,interposing a variable counter electromotive force in such derivedfield-circuit and altering said counter electromotive force by means ofthe resultant effect of currents flowing in series and in parallel withthe main or controlled circuit, substantially as described.

3. The method of controlling the generation of current which consists ininterposing in the field-circuit of the generator, a variable factorcontrolling the magnetic field of said generator, altering said factorto suit the condition of the working circuit of said generator, andtransferring to other portions of the system the excess of energydiverted to the field-circuit of the generator, substantially asdescribed.

4. The herein-described method of operating a system of electricaldistribution, which consists in interposing a variable counterelectromotive force in the field-circuit of the main generator, alteringsaid counter electromotive force by means of the resultant effect ofcurrents flowing in series and in parallel with the controlled circuit,and diverting any excess of energy from the field-circuit of saidgenerator to the main circuit thereof.

5. In a system of electrical distribution, the combination with adynamo-electric machine having a field-circuit in shunt with andderiving current from the main circuit of the machine, of a deviceconnected therewith exerting a variable electromotive force adapted torespond to changes in the current flowing in the main circuit, andmeans, controlled by the electromotive force of said device, for varyingthe electromotive force of said dynamo corresponding to variations ofthe current flowing in the main circuit, substantially as described.

6. The combination with a dynamo-electric machine having a field-circuitin shunt with and deriving energy from the main circuit thereof, of asecondary dynamo-electric machine included in the field-circuit of saidfirstmentioned dynamo adapted without change of speed to vary thecurrent flowing in said fieldcircuit,whereby the current furnished toeach translating deviceis maintainedsubstantially constant,substantially as described.

7. The combination with a dynamo-electric machine having a field-circuitin shunt with, and deriving energy from, the main circuit thereof, ofanother dynamo included in said shunted field-circuit, adapted to varythe current flowing in said field-circuit and means for transmitting tothe main circuit the excess of energy diverted to the field-circuit ofthe first-mentioned dynamo, substantially as described.

8. In a multiple-arc system of electrical distribution, the combinationwith a main dynamo-electric machine or generator for supplying currentthereto, of a secondary dynamo-electric machine connected in thefieldcircuit of the main generator,compound windings provided for thesecondary dynamo-electric machine connected respectively in series withand in a branch across the mains of the system adapted to alter thecounter electromotive force of the said secondary dynamo, and afield-circuit for the main generator in shunt with the main or workcircuit and in cluding the armature of said secondary dynamo, wherebythe field strength of the main dynamo is regulated to compensate forvariations of load, substantially as described.

9. In a multiple-arc systen1,of electrical distribution, the combinationwith a main dynamo-electric machine adapted to supply current thereto,of a second dynamo-electric ma chine connected in the field-circuit ofthe main generator, compound field-windings provided for the seconddynamo-electric machine connected respectively in series with and in abranch across the mains of the system, and means for transferring toother positions of the said system the excess of energy diverted to thefield-circuit of the main generator, substantially as described.

10. The combination with a dynamo-electric machine A, of a field-circuitfor said main dynamo in shunt with the main or work circuit thereof, asecondary dynamo 0 included in said shunt field-circuit,distributing-mains connected with the dynamo A, and compoundfield-windings for dynamo O, the said fieldwindings being connectedrespectively in series with said distributing-mains and in a bridgeacross the same, whereby the dynamo O is adapted to vary the currentflowing in the field-circuit of dynamo A to compensate for variations ofload in the main circuit, substantially as described.

11. In a system of electrical distribution, the combination with a maindynamo-electric machine A, of mains D D connected therewith, afield-winding B for said dynamo connected in shunt with the mains, asecondary dynamo C, the armature whereof is included in theshunt-circuit which supplies the fieldwinding B, and differentialfield-windings O C for the secondary dynamo connected respectively inseries and in parallel with the said mains, substantially as and for thepurpose set forth.

12. In a system of electrical distribution, the combination with a maindynamo-electric machine A, of mains D D connected therewith, afield-circuit for said main dynamo connected in shunt with said mains, asecondary dynamo (J, the armature whereof is included in circuit withthe said shunt field-winding of the main dynamo, differentialfieldwvindings O O for the said secondary dynamo, connected respectivelyin series and in parallel with the mains D D, and a mechanicalconnection between the dynamos A and O, substantially as and for thepurpose set forth.

In witness whereof I hereunto subscribe my name this 11th day of March,A. D. 1897.

CHARLES A. BROWN.

I'Vitnesses:

GEORGE L. CRAGG, A. L. LAWRENCE.

